>Either way, this idea that you subscribe to a stream makes reconnection and place-holding (cursor) semantics difficult This is true. It's also a problem if yo

>Either way, this idea that you subscribe to a stream makes reconnection and place-holding (cursor) semantics difficult This is true. It's also a problem if you drop a packet - you need to build up state again on the client side. If you're writing a book about event sourcing, I should think you'll spend a good deal of time covering trading systems and order books since these are an area where event sourcing (AIUI) has been used for decades.